Juvenile idiopathic arthritis of the knee: is contrast needed to score disease activity when using an augmented MRI protocol comprising PD-weighted sequences?

OBJECTIVE: To compare unenhanced versus enhanced knee joint magnetic resonance imaging (MRI) to assess disease activity of juvenile idiopathic arthritis (JIA). METHODS: Fifty-three knee joint MRI examinations were performed on a 3-Tesla system in 27 patients (age: 11.40 ± 3.61 years; 21 females, 6 males). MRI protocols comprised PD-weighted sequences in addition to the widely used standard protocol. JIA subgroups comprised oligoarticular arthritis (n = 16), extended oligoarthritis (n = 6), rheumatoid factor-negative polyarticular arthritis (n = 3), enthesitis-related arthritis (n = 1), and psoriatic arthritis (n = 1). MR images were retrospectively analyzed by 3 experienced radiologists in two readings, using JAMRIS (juvenile arthritis MRI scoring) system and a modified IPSG (international prophylaxis study group) classification. In the first reading session, only unenhanced MR images were evaluated. In a second reading session, all images before and after contrast medium application were included. In order to avoid bias, an interval of at least 2 weeks was set between the two readings. The clinical JADAS10 (juvenile arthritis disease activity score) was calculated including clinical assessment and laboratory workup and correlated with MRI scores. Statistical analysis comprised Pearson's correlation for correlating two scoring results of unenhanced and the enhanced MRI, intra-class correlation coefficient (ICC) for inter- and intra-reader agreement. Diagnostic accuracy was calculated using ROC (receiver operating characteristics) curve analysis. RESULTS: Inter-reader agreement determined by ICC for unenhanced and enhanced MRI scores for IPSG was moderate (0.65, 95% CI 0.51-0.76, and 0.62, 95% CI 0.48-0.75) and high for JAMRIS (0.83, 95% CI 0.75-0.89, and 0.82, 95% CI 0.74-0.89). Intra-reader agreement was good to very good for JAMRIS (0.85 95% CI 0.81-0.88, 0.87 95% CI 0.83-0.89 and 0.96 95% CI 0.92-0.98) and IPSG (0.76 95% CI 0.62-0.86, 0.86 95% CI 0.77-0.92 and 0.92 95% CI 0.86-0.96). Scores of unenhanced MRI correlated with contrast-enhanced MRI: JAMRIS (r = 0.97, R2 = 0.93, p < 0.01), modified IPSG (r = 0.95, R2 = 0.91, p < 0.01). When using JADAS10 as a reference standard, moderate accuracy for both unenhanced and enhanced MRI scores was noted: JAMRIS (AUC = 0.68, 95% CI 0.51-0.85, and AUC = 0.66, 95% 0.49-0.82), IPSG score (AUC = 0.68, 95% 0.50-0.86, and AUC = 0.61, 95% 0.41-0.81). CONCLUSIONS: Our results suggest that contrast agent application could be omitted in JIA patients with an augmented knee MRI protocol comprising PD-weighted sequence. KEY POINTS: • Unenhanced MRI can detect disease activity of the knee joint in patients with JIA with equally high accuracy compared to contrast-enhanced MRI. • The intra- and inter-reader agreement was high for unenhanced and enhanced MRI JAMRIS scores, which indicate relatively good applicability of the scoring system, even for less experienced readers. • When using the clinical JADAS10 as a reference standard for the detection of disease activity, moderate accuracy for both unenhanced and enhanced MRI scores, both JAMRIS and IPSG, was noted, which might be caused by the fact that the majority of patients had either no or minimal clinical disease activity.

[Consensus-Based Guidelines for Diagnosis, Prevention and Treatment of Tuberculosis in Children and Adolescents - A Guideline on Behalf of the German Society for Pediatric Infectious Diseases (DGPI)]. / S2k-Leitlinie zur Diagnostik, Prävention und Therapie der Tuberkulose im Kindes- und Jugendalter.

Recently, epidemiological data shows an increase of childhood tuberculosis in Germany. In addition to this, drug resistant tuberculosis becomes more frequent. Therefore, diagnosis, prevention and therapy in childhood and adolescence remain a challenge. Adult guidelines do not work for children, as there are age specific differences in manifestation, risk of progression and diagnostic as well as therapeutic pathways.The German Society for Pediatric Infectious Diseases (DGPI) has initiated a consensus-based (S2k) process and completed a paediatric guideline in order to improve and standardize care for children and adolescents with tuberculosis exposure, infection or disease.Updated dosage recommendations take age dependant pharmacokinetics in the treatment of drug sensitive but also drug resistant tuberculosis in account. In addition to this, there is a detailed chapter on perinatal exposure and disease as well as extrapulmonary manifestations.

Imaging of chronic inflammatory bowel disease with 18F-FDG PET in children and adolescents.

Standard for diagnosis of inflammatory bowel disease (IBD) is the endoscopy of the stomach and the intestine. Aim of this study was to determine the value of 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) in pediatric patients with mild to moderate IBD.We included 23 children and adolescents between 8 and 17 years (median 15 years, 13 boys, 10 girls) in this retrospective study in a routine clinical setting. Diagnoses were Crohn's disease in 19 and ulcerative colitis in 4 cases.3 children had a conventional FDG-PET, 20 patients a combined FDG-PET-computed tomography exam. All children had upper and lower intestinal endoscopy with biopsy and a Hydro-MRI exam to assess the jejunum and proximal ileum. The gastrointestinal tract was divided in 7 segments: Stomach plus duodenum, jejunum and proximal ileum, terminal ileum, cecum plus ascending colon, transverse colon, descending colon, and rectosigmoid.Superficial gastric lesions were missed, gastric ulcerations were detected. For the stomach, the sensitivity was 0.25, the specificity was 1.00, the positive predictive value was 1.00, for the lower intestine (terminal ileum and colon) the values were 0.74, 0.88, and 0.96; for the terminal ileum 0.89, 0.75 and 0.94, respectively.The sensitivity and specificity for of ileal and colonic lesions is high. FDG-PET has to be discussed as a tool for the determination of extent and degree of inflammation, especially in those parts of the small bowel that are not accessible to endoscopy. This has to be weighed against the additional radiation exposure administrated.

Partial splenic embolization as an alternative to splenectomy in hypersplenism--single center experience in 16 years.

PROBLEM: In young patients with hypersplenism splenectomy implies a lifelong increased risk for post-splenectomy infection. Especially in children, whose immune system is not yet completely matured, the risk for some bacterial infection may increase after splenectomy because the spleen helps to defend against encapsulated bacteria like pneumococci, meningococci and haemophilus influenzae. We present partial splenic embolization as an alternative to surgical splenectomy. METHOD: Partial splenic embolization was performed in 17 patients from 1-31 years with hypersplenism of various etiologies and was achieved by selective catheterization of splenic arteries and injection of 150-355 µm polyvinyl alcohol particles (Ivalon (®)). After the intervention the patients received an intensified analgesic regimen and antibiotics to avoid concurrent infectious complications. RESULTS: Partial splenic embolization represented between 30-60% of the splenic volume and was followed in general by an immediate increase of all blood cells and symptoms of hypersplenism were reduced. In 2 patients the procedure was repeated because the result of the first embolization was insufficient in one patient and became necessary in another in the long run. Post-procedural side effects included fever, abdominal pain, ascites and pleural effusions. There were no acute infections in any patient. CONCLUSION: Our monoinstitutional experiences over 16 years offer, partial splenic embolization in patients with hypersplenism from miscellaneous reasons as a low-risk alternative to surgical splenectomy. The procedure can be repeated as necessary, but it is always a temporary palliation depending on the underlying disease which often leads to liver transplantation. Using intensive analgesia and antibiotics side effects were tolerable, and patients could be discharged after a few days.

Consecutive bilateral proximal tibial fractures after minor sports trauma.

INTRODUCTION: Fractures of the proximal tibia are infrequent during childhood and adolescence. However, intra-articular fractures, growth plate separations and metaphyseal fractures do appear. CASE REPORT: An obese adolescent male suffered from consecutive bilateral fractures of the tibia within 6 months of each after minor sports trauma. On the left side, the injury presented as a epiphyseal separation of the Salter-Harris I type; on the right side, as a transitional two-plane fracture. Both injuries were treated by percutaneous screwing and healed without any signs of posttraumatic growth disorder. DISCUSSION: Although proximal tibial injuries are rare, they frequently seem to appear bilaterally after inadequate trauma. A causal connection to morphological changes prior to physeal closure can be assumed.

Ultrasound in diagnosis of fractures in children: unnecessary harassment or useful addition to X-ray?

PURPOSE: Handling children with trauma is often very difficult, as the signs and the exact location of the fracture are sometimes unclear. The aim of this study was to compare ultrasound and X-ray for the identification of fractures. MATERIALS AND METHODS: In this study 653 patients from newborn to 17 years old (mean age 4.4 years) with nonspecific clinical signs or clinically indistinct fracture location were examined initially with ultrasound. After identification of the fracture by ultrasound, an X-ray exam of the predefined region followed. In cases of negative ultrasound an X-ray exam was performed not focused on a predefined region. RESULTS: Examinations of 726 parts of the body revealed 308 fractures. 266 fractures were identified by both ultrasound and X-ray, 20 exclusively by ultrasound, 21 exclusively by X-ray. One maxillary fracture was missed. The sensitivity was 92.9% for ultrasound and 93.2% for X-ray, and the specificity was 99.5% (ultrasound) and 99.8% (X-ray). Ultrasound was superior to X-ray on the clavicle, but the opposite was true in the lower limb. In 8.4% of the patients ultrasound helped us to reduce the number of X-rays. CONCLUSION: Ultrasound is comparable to X-ray for the detection of fractures. Ultrasound should be the first imaging method in children with trauma and nonspecific clinical signs or indistinct location of pain, followed by X-ray exams of the predefined region.

[Efficient imaging of elbow injuries in children and adolescents]. / Effiziente Bildgebung von Ellenbogenverletzungen bei Kindern und Jugendlichen.

The purpose of imaging of the elbow region in children after acute trauma is the diagnosis of injuries that require further treatment. Basic diagnostic consists of standard X-rays of the elbow in two planes. Exceptions can be made in the case of nursemaid's elbow lesion (subluxation of the radial head; pronation douloureuse; Chassaignac lesion) with unambiguous mechanism of the trauma where no X-ray imaging is needed and in heavily dislocated fractures for which one plane can be sufficient. X-ray imaging of the uninjured side is obsolete. Follow-up X-ray imaging is only allowed if consequences for the further treatment are expected. Ultrasound may partially replace X-rays in the future if further standardization of this technique can be achieved. MRI provides additional information in acute trauma which, however, remains currently without consequences for the further treatment strategy.

[Trabecular bone mineral density measured by quantitative CT of the lumbar spine in children and adolescents: reference values and peak bone mass]. / Trabekuläre Knochendichte der Lendenwirbelsäule bei Kindern und Jugendlichen in der quantitativen CT: Referenzwerte und Peak Bone Mass.

PURPOSE: The aim of this study was to assess bone density values in the trabecular substance of the lumbar vertebral column in children and young adults in Germany from infancy to the age of peak bone mass. MATERIALS AND METHODS: We performed quantitative computed tomography (QCT) on the first lumbar vertebra in 28 children and adolescents without diseases that may influence bone metabolism (15 boys, 13 girls, mean ages 11 and 8 years, respectively). We also measured 17 healthy young adults (9 men, 8 women, mean ages 20 and 21 years). We used a Somatom Balance Scanner (Siemens, Erlangen) and the Siemens Osteo software. Scan parameters: Slice thickness 1 cm, 80 kV, 81 or 114 mAs. We measured the trabecular bone density and the area and height of the vertebra and calculated the volume and content of calcium hydroxyapatite (Ca-HA) in the trabecular substance of the first lumbar vertebra. RESULTS: Prepubertal boys had a mean bone density of 148.5 (median [med] 150.1, standard deviation [SD] 15.4) mg/Ca-HA per ml bone, and prepubertal girls had a mean density of 149.5 (med 150.8, SD 23.5) mg/ml. We did not observe a difference between prepubertal boys and girls. After puberty there was a significant difference (p < 0.001) between males and females: Mean density (male) 158.0, med 162.5, SD 24.0 mg/ml, mean density (female) 191.2, med 191.3, SD 17.7 mg/ml. The Ca-HA content in the trabecular bone of the first lumbar vertebra was 1.1 (med 1.1, SD 0.5) g for prepubertal boys and 1.1 (0.9, 0.4) g for prepubertal girls. For post-pubertal males, the mean Ca-HA content was 3.5 g, med 3.5, SD 0.5 g, and for post-pubertal females, the mean content was 2.8, med 2.7, SD 0.4 g. CONCLUSION: The normal trabecular bone mineral density is 150 mg/ml with a standard deviation of 20 mg/ml independent of age or gender until the beginning of puberty. Peak bone mass (bone mineral content) in the trabecular substance of the lumbar vertebral column is higher in males than in females, and peak bone density is higher in young female adults than in young male adults.

[Assessment of bone density in children and adolescents by quantitative CT of one lumbar vertebra only]. / Messung der Knochendichte bei Kindern und Jugendlichen mittels quantitativer CT an nur einem Lendenwirbelkörper.

AIM: The aim of this study was to determine whether measuring the trabecular bone density in one lumbar vertebra (L) instead of three has an effect on the assessment of bone density in children. MATERIALS AND METHODS: Bone density was measured in 70 patients (38 male, 32 female), ages 1 to 22 years (mean age 12.4, median 13 years) using a Somatom Balance Scanner (Siemens). The trabecular bone density was measured (1-cm slice, 80 kV, 81 mAs) in L1 through L3. RESULTS: The mean bone density in the lumbar vertebrae was 139.9 mg/ml calcium-hydroxylapatite per ml bone in L1, 133.9 in L2, and 131.7 in L3, and the mean of all three vertebrae was 135.2 mg/ml. Measurements in L1 were 4.7 mg/ml (standard deviation [SD] 4.7 mg/ml) above the mean value of the three upper lumbar vertebrae. The density in L2 was 1.3 mg/ml below the mean (SD 3.1 mg/ml). On average, L3 was 3.5 mg/ml below the mean (SD 4.6 mg/ml). This minor systematic deviation in the measurement values for the individual vertebrae from the mean value was so low that there was no statistical evidence for a deviation from an ideal regression line. CONCLUSIONS: When using an adequate technique, especially accurate analysis of the topogram (scout view) and the tomogram, measurement of the bone density of one lumbar vertebra provides satisfactory information regarding the trabecular bone density in children, but the values differ in the three upper lumbar vertebrae. The bone density of L2 is close to the mean of the upper three vertebrae. In the case of pathologic values or a pathologic trabecular pattern, three vertebrae should be measured.

Esophageal foreign bodies: removal of the new euro coins with a magnet tube.

AIM OF THIS STUDY: We use a magnet tube to extract esophageal coins. It is smaller than the Foley balloon catheter and easier to handle than a forceps. We present the magnet tube maneuver and investigate whether the new euro coins can be removed with a magnet. METHOD: We take radiographs of coins and measure the adhesive force of the magnet and compare with the 10 Pfennig German coin which we most often removed successfully from the esophagus. RESULTS: The 1, 2, and 5 euro cent pieces are magnetic and can possibly be removed with a magnet tube. The non-magnetic pieces can be identified based on the rim and size. DISCUSSION: When an esophageal foreign body is not round and smooth like a coin, the fluoroscopic guided procedure becomes more risky with respect to mucosal injury. When a large object is stuck in the esophagus for more than 24 hours, an endoscopy must be considered to rule out any severe damage to the esophageal wall.

Measurement of torsion angles of long finger bones using computed tomography.

OBJECTIVE: Rotational dislocation at the fracture site is a complication of long finger bone fractures of the metacarpals and phalanges. To evaluate such deformities, we performed CT of the articular surfaces of these bones to demonstrate the torsion angles. DESIGN: We evaluated 10 pairs of cadaver hands. These were placed flat, with the bones of interest perpendicular to the gantry to acquire axial images. The torsion of the long bone axes was defined as the angle between a tangent positioned parallel to the proximal articular surface and a tangent parallel to the distal articular surface of individual bones. RESULTS: The maximum difference between repeated measurements was 4 degrees. Intraobserver differences measured between right and left hands are less than 3 degrees. CONCLUSION: Side differences in torsion angles exceeding 3 degrees are strongly suspicious of a malrotation after fracture. These measurements might help to plan derotational osteotomy and assess the results of therapy.

Feasibility of MRI in the diagnosis of acute diverticulitis: initial results.

PURPOSE: The purpose of this study was to evaluate MRI as a diagnostic tool in patients with suspected acute sigmoid diverticulitis. Furthermore, we sought to develop an optimal imaging protocol in these patients. PATIENTS AND METHODS: Eleven patients with suspected acute diverticulitis were included in the study. All patients were imaged in a 1.0 T clinical scanner using a body-array coil. Imaging sequences were single-shot TSE, HASTE-, STIR- and TrueFisp- sequence. All were obtained in the frontal plane. The diagnosis was verified by a single experienced investigator, using ultrasound, and overall clinicopathological outcome. RESULTS: MRI enabled visualization of signs of an acute diverticulitis in all patients. However, the diagnosis of acute diverticulitis was obtained in 10 patients only. The mean imaging time was 17.5+/-5.5 min. STIR- and TrueFisp-sequences alone displayed all findings, e.g pericolonic exsudation, edema and segmental narrowing, whereas SSTSE and HASTE-sequences showed no additional information. Therefore, it appeared that the imaging protocol could be restricted to STIR- and TrueFisp-sequences. CONCLUSION: MRI is feasible as a fast, accurate and investigator-independent diagnostic tool in patients with suspected acute diverticulitis. To prove its value in comparison to computed tomography or ultrasound, further studies are needed.

Magnetic resonance colonography and virtual magnetic resonance colonoscopy with the 1.0-T system: a feasibility study.

RATIONALE AND OBJECTIVES: An ex vivo study and a clinical, prospective, patient study were undertaken to evaluate the feasibility of magnetic resonance (MR) colonography with a 1.0-T system. METHODS: An ex vivo colon model was scanned. A cleaned pig colon was prepared with six simulated sessile polyps (diameters of 4-12 mm) and one simulated pedunculated polyp (diameter of 5 mm). Subsequently, five patients (aged 39-81 years; four women, one man) were examined with MR colonography, immediately followed by endoscopic colonoscopy. After preparation for colonoscopy, the colon was filled with a Gd-DTPA/water solution (1:100). A breath-hold 3D gradient-echo sequence was acquired in both the prone and supine positions and after intravenous Gd-DTPA administration. Images were analyzed interactively by using multiplanar projections, maximum-intensity projection, and a virtual endoscopic view. The MR results were compared with the findings of the fiberoptic endoscopy. RESULTS: All seven simulated lesions of the colon model could be detected by MR imaging. In one patient, an advanced colon cancer as well as an additional small polyp was depicted. In the other four patients, single polyps with a diameter of 1 to 2.5 cm and a large adenoma were visualized by MR colonography. Contrast enhancement of the polyps was noted only after subtraction. CONCLUSIONS: The 1.0-T system is feasible for MR colonography. Reduced requirements for hardware could contribute to establish the novel technique as a screening method for colorectal polyps.

[Pulmonary, nodular cavernous, calcifying form of amyloidosis]. / Pulmonale, noduläreinschmelzende, kalzifizierende Form der Amyloidose.

We report a rare case of pulmonary nodular amyloidosis featuring all typical morphologic alterations associated with this disease; multiple amyloidomas, calcification and cavernous transformation were present. Definite diagnosis was established histologically with CT-guided biopsy. The different types of pulmonary amyloidosis and their radiological appearances are described and discussed.

[Standardized enteroclysis. Monitoring of intra-lumen pressure in 3 different patient groups]. / Standardisierte Enteroklyse. Registrierung des intraluminalen Drucks in drei unterschiedlichen Patientenkollektiven.

PURPOSE: Monitoring of intraluminal pressure in standardized enteroclysis. MATERIAL AND METHODS: Pressure monitoring with a double-lumen tube during fluoroscopy-guided adjustment of contrast media instillation rate due to small bowel motility and contrast media transport of 67 patients. Stratification according to patient data and findings in enteroclysis: Crohn's disease (n = 12), non-inflammatory disease (n = 35) and irritable bowel syndrome (n = 20). RESULTS: The amount, instillation period and rate of contrast media and distension media were not statistically different within the study population. Crohn's disease patients showed elevated intraluminal pressure at the end of the distension phase (47.94 +/- 10.42 cm H2O versus 38.03 +/- 10.08 and 39.55 +/- 9.74 cm H2O, respectively, P = 0.0099), as well as at the end of the examination (48.59 +/- 10.42 cm H2O versus 39.66 +/- 6.52 and 35.67 +/- 8.28 cm H2O, P = 0.0002). In comparison with both other patient groups, maximum intraluminal pressure in Crohn's disease is higher and totals 51.75 +/- 9.94 cm H2O versus 43.00 +/- 6.20 and 39.55 +/- 9.74 cm H2O, P = 0.0010. Patients with Crohn's disease require a longer instillation period of distension media (28.05 +/- 12.82 min, not statistically significant). CONCLUSION: Intraluminal pressure differs in standardized enteroclysis with fluoroscopy-guided instillation rate adjustment. Irrespective of stenosis or acute inflammation, patients with Crohn's disease show a higher intraluminal pressure compared to patients with non-inflammatory disease or irritable bowel syndrome.

[Mortality and morbidity conference in radiology]. / Mortalitäts- und Morbiditätskonferenz in der Radiologie.

PURPOSE: To establish a morbidity and mortality conference in a radiology department as an instrument of quality assurance. METHODS: Since April 1995 a monthly conference is held in the radiology department. Complications of invasive diagnostic procedures (angiography and biopsy) and minimal invasive interventions are presented. Cases of morbidity (major complications) and mortality (deceased patients, who were examined or treated in the radiology department before) are discussed. The identification of cases was possible due to a data base that included all such procedures prospectively. RESULTS: Twenty cases of major complications were identified and discussed during 18 morbidity and mortality conferences in 1996 and 1997. Out of the 9 patients who died in our hospital and previously had an interventional procedure in the radiology department, one case was identified as being procedure-related. An analysis of this case was performed. CONCLUSION: With a formalised structure of case detection, the morbidity and mortality conference becomes a tool of a complete analysis of complications and a meaningful instrument for the solution of problems concerning procedure-related complications.

[Cleavage of dipeptides in tissues of the rat exemplified by glycyl-L-tyrosine. Development of a method for measuring dipeptidase activities and kinetic properties]. / Die Spaltung von Dipeptiden in Geweben der Ratte am Beispiel von Glycyl-L-Tyrosin. Entwicklung einer Methode zur Messung von Dipeptidase-Aktivitäten und kinetischen Eigenschaften.

Glycyl-L-tyrosine is hydrolysed by tissue homogenates of rat kidney, lung, liver, muscle and by blood. Methods of peptidase assay are critically examined and kinetic data are given for the tissues.